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91.
Context
Health care technological evolution through new drugs, implants and other interventions is a key driver of healthcare spending. Policy makers are currently challenged to strengthen the evidence for and cost-effectiveness of reimbursement decisions, while not reducing the capacity for real innovations. This article examines six cases of reimbursement decision making at the national health insurance authority in Belgium, with outcomes that were contested from an evidence-based perspective in scientific or public media.Methods
In depth interviews with key stakeholders based on the adapted framework of Davies allowed us to identify the relative impact of clinical and health economic evidence; experience, expertise & judgment; financial impact & resources; values, ideology & political beliefs; habit & tradition; lobbyists & pressure groups; pragmatics & contingencies; media attention; and adoption from other payers & countries.Findings
Evidence was not the sole criterion on which reimbursement decisions were based. Across six equivocal cases numerous other criteria were perceived to influence reimbursement policy. These included other considerations that stakeholders deemed crucial in this area, such as taking into account the cost to the patient, and managing crisis scenarios. However, negative impacts were also reported, in the form of bypassing regular procedures unnecessarily, dominance of an opinion leader, using information selectively, and influential conflicts of interest.Conclusions
‘Evidence’ and ‘negotiation’ are both essential inputs of reimbursement policy. Yet, purposely selected equivocal cases in Belgium provide a rich source to learn from and to improve the interaction between both. We formulated policy recommendations to reconcile the impact of all factors identified. A more systematic approach to reimburse new care may be one of many instruments to resolve the budgetary crisis in health care in other countries as well, by separating what is truly innovative and value for money from additional ‘waste’. 相似文献92.
Chytridiomycosis has been identified as a major cause of global amphibian declines. Despite widespread evidence of Batrachochytrium dendrobatidis infection in South African frogs, sampling for this disease has not focused on threatened species, or whether this pathogen poses a disease risk to these species. This study assessed the occurrence of Bd-infection in South African Red List species. In addition, all known records of infection from South Africa were used to model the ecological niche of Bd to provide a better understanding of spatial patterns and associated disease risk. Presence and prevalence of Bd was determined through quantitative real-time PCR of 360 skin swab samples from 17 threatened species from 38 sites across the country. Average prevalence was 14.8% for threatened species, with pathogen load varying considerably between species. MaxEnt was used to model the predicted distribution of Bd based on 683 positive records for South Africa. The resultant probability threshold map indicated that Bd is largely restricted to the wet eastern and coastal regions of South Africa. A lack of observed adverse impacts on wild threatened populations supports the endemic pathogen hypothesis for southern Africa. However, all threatened species occur within the limits of the predicted distribution for Bd, exposing them to potential Bd-associated risk factors. Predicting pathogen distribution patterns and potential impact is increasingly important for prioritising research and guiding management decisions. 相似文献
93.
94.
Peter Riedlberger Stefanie Brüning Dirk Weuster-Botz 《Bioprocess and biosystems engineering》2013,36(7):927-935
The evaluation of mixing quality is an important factor for improving the geometry of stirred-tank reactors and impellers used in bioprocess engineering applications, such as the enzymatic hydrolysis of plant materials. Homogeneity depends on different factors, including the stirrer type and the reactor type (e.g., ratio of diameter/height, ratio of impeller tip diameter/reactor diameter) with or without baffles. This study compares two impellers for enzymatic hydrolysis of suspensions of biomass particles on a milliliter scale. Both impellers were derived from industrially relevant geometries, such as blade and grid stirrers, although the geometry of the second stirrer was slightly modified to an asymmetric shape. The stirrers were investigated with different stirrer–reactor configurations. This was done experimentally and with the aid of computational fluid dynamics. The flow field, mixing numbers, power characteristics and initial conversion rates of sugars were considered to compare the two stirrers. The simulated mixing numbers and power characteristics in baffled and unbaffled milliliter-scale reactors were found to be in good agreement with the measured mixing times and power consumption. The mixing numbers required to reach homogeneity were much higher for the symmetric impeller and remained at least twice as high as the mixing numbers required when using the asymmetric impeller. The highest initial sugar releases from milled corn stover suspensions were achieved with the asymmetric impeller shape. Regardless of the differences in the flow fields or mixing times, diverging enzymatic sugar releases could be confirmed for Newtonian media only. 相似文献
95.
Benjamin Steeb Beatrice Claudi Neil A. Burton Petra Tienz Alexander Schmidt Hesso Farhan Alain Mazé Dirk Bumann 《PLoS pathogens》2013,9(4)
Pathogen access to host nutrients in infected tissues is fundamental for pathogen growth and virulence, disease progression, and infection control. However, our understanding of this crucial process is still rather limited because of experimental and conceptual challenges. Here, we used proteomics, microbial genetics, competitive infections, and computational approaches to obtain a comprehensive overview of Salmonella nutrition and growth in a mouse typhoid fever model. The data revealed that Salmonella accessed an unexpectedly diverse set of at least 31 different host nutrients in infected tissues but the individual nutrients were available in only scarce amounts. Salmonella adapted to this situation by expressing versatile catabolic pathways to simultaneously exploit multiple host nutrients. A genome-scale computational model of Salmonella in vivo metabolism based on these data was fully consistent with independent large-scale experimental data on Salmonella enzyme quantities, and correctly predicted 92% of 738 reported experimental mutant virulence phenotypes, suggesting that our analysis provided a comprehensive overview of host nutrient supply, Salmonella metabolism, and Salmonella growth during infection. Comparison of metabolic networks of other pathogens suggested that complex host/pathogen nutritional interfaces are a common feature underlying many infectious diseases. 相似文献
96.
Donato Spoltore Wibren D. Oosterbaan Samira Khelifi John N. Clifford Aurelien Viterisi Emilio Palomares Marc Burgelman Laurence Lutsen Dirk Vanderzande Jean Manca 《Liver Transplantation》2013,3(4):466-471
The non‐geminate recombination of charge carriers in polymer‐fullerene solar cells has been modeled in the last few years with a trap‐assisted recombination model, which states that the apparent recombination order depends on the concentration of trapped charges tailing into the band gap. Higher concentrations of trapped charges lead to higher apparent recombination orders. In this work, the mass fraction f of highly crystalline nanofibrillar P3HT to the total P3HT content in P3HT:PCBM solar cells is consistently varied, controlling the temperature of a nanofibers‐P3HT casting dispersion. A systematic study of the apparent recombination order, measured with a transient photovoltage technique, as a function of f is presented. A correlation is shown between the apparent recombination order, the P3HT crystallinity, and the trap concentration in the band gap measured with an admittance spectroscopy technique. 相似文献
97.
Synthetic biology (SynBio) is a global endeavour with research and development programs in many countries, and due (in part) to its multi-use characteristics it has potential to improve global health in the area of vaccine development, diagnostics, drug synthesis, and the detection and remediation of environmental toxins. However, SynBio will also concurrently require global governance. Here we present what we have learnt from the articles in this Special Issue, and the workshop we hosted in The Hague in February of 2012 on SynBio, global health, and global governance that generated many of the papers appearing here. Importantly we take the notion of ‘responsible research and innovation’ as a guiding perspective. In doing so our understanding of governance is one that shifts its focus from preventing risks and other potential negative implications, and instead is concerned with institutions and practices involved in the inclusive steering of science and technology towards socially desirable outcomes. We first provide a brief overview of the notion of global health, and SynBio’s relation to global health issues. The core of the paper explores some of the dynamics involved in fostering SynBio’s global health pursuits; paying particular attention to of intellectual property, incentives, and commercialization regimes. We then examines how DIYbio, Interactive Learning and Action, and road-mapping activities can be seen as positive and productive forms of governance that can lead to more inclusive SynBio global health research programs. 相似文献
98.
99.
Peter Schierack Stefan R?diger Christoph Kuhl Rico Hiemann Dirk Roggenbuck Ganwu Li J?rg Weinreich Enrico Berger Lisa K. Nolan Bryon Nicholson Antje R?mer Ulrike Fr?mmel Lothar H. Wieler Christian Schr?der 《PloS one》2013,8(4)
We established an automated screening method to characterize adhesion of Escherichia coli to intestinal porcine epithelial cells (IPEC-J2) and their probiotic activity against infection by enteropathogenic E. coli (EPEC). 104 intestinal E. coli isolates from domestic pigs were tested by PCR for the occurrence of virulence-associated genes, genes coding for resistances to antimicrobial agents and metals, and for phylogenetic origin by PCR. Adhesion rates and probiotic activity were examined for correlation with the presence of these genes. Finally, data were compared with those from 93 E. coli isolates from wild boars.Isolates from domestic pigs carried a broad variety of all tested genes and showed great diversity in gene patterns. Adhesions varied with a maximum of 18.3 or 24.2 mean bacteria adherence per epithelial cell after 2 or 6 hours respectively. Most isolates from domestic pigs and wild boars showed low adherence, with no correlation between adhesion/probiotic activity and E. coli genes or gene clusters. The gene sfa/foc, encoding for a subunit of F1C fimbriae did show a positive correlative association with adherence and probiotic activity; however E. coli isolates from wild boars with the sfa/foc gene showed less adhesion and probiotic activity than E. coli with the sfa/foc gene isolated from domestic pigs after 6 hour incubation.In conclusion, screening porcine E. coli for virulence associated genes genes, adhesion to intestinal epithelial cells, and probiotic activity revealed a single important adhesion factor, several probiotic candidates, and showed important differences between E. coli of domestic pigs and wild boars. 相似文献
100.
Thomas Vercruysse Eline Boons Tom Venken Els Vanstreels Arnout Voet Jan Steyaert Marc De Maeyer Dirk Daelemans 《PloS one》2013,8(4)
HIV-1 Rev is the key protein in the nucleocytoplasmic export and expression of the late viral mRNAs. An important aspect for its function is its ability to multimerize on these mRNAs. We have recently identified a llama single-domain antibody (Nb190) as the first inhibitor targeting the Rev multimerization function in cells. This nanobody is a potent intracellular antibody that efficiently inhibits HIV-1 viral production. In order to gain insight into the Nb190-Rev interaction interface, we performed mutational and docking studies to map the interface between the nanobody paratope and the Rev epitope. Alanine mutants of the hyper-variable domains of Nb190 and the Rev multimerization domains were evaluated in different assays measuring Nb190-Rev interaction or viral production. Seven residues within Nb190 and five Rev residues are demonstrated to be crucial for epitope recognition. These experimental data were used to perform docking experiments and map the Nb190-Rev structural interface. This Nb190-Rev interaction model can guide further studies of the Nb190 effect on HIV-1 Rev function and could serve as starting point for the rational development of smaller entities binding to the Nb190 epitope, aimed at interfering with protein-protein interactions of the Rev N-terminal domain. 相似文献